A person familiar with the situation said Bostic was fined $21,000 for the hit during last week's preseason game against San Diego.

The person spoke Wednesday on the condition of anonymity because the fine has not been announced.

"I'm just finding out about all of this stuff," Bostic said. "I really haven't even thought about it to tell you the truth. I'm going to focus on this week and the game plan."

A second-round draft pick out of Florida last spring, Bostic drilled the Chargers' Mike Willie as he turned trying to catch a pass, jarring the ball from the receiver on a play that was ruled an incompletion. No penalty was called.

Bostic was punished for delivering a hit against a defenseless receiver while lowering his head and making forcible contact with the top or crown of his helmet.

"Obviously, it's a bang-bang play," he said. "But when we target the ballcarrier, it's getting your head across, making sure you're not on the back side so he can run through the tackle and keep your feet running."

Bostic sidestepped the question when asked if he would appeal, saying, "Right now, I don't even know the whole process. Like I said, I'm new to the NFL. This is my first year, so I don't know how this process exactly works. I've got to find out more about it and figure out exactly how everything is going to play out."

"I can only address what I saw, and that his head was up and he hit with his shoulder and he ran through the player the way we're trying to teach these guys to play every day, to be safe for themselves and for the guys that they are hitting, to do it the right way," Trestman said.

Seven-time Pro Bowl linebacker Lance Briggs, who broke the news about the fine on Twitter, wasn't sure what Bostic could have done differently. Actually, he had an idea.

"He could have allowed the receiver to run him over - that's another technique," Briggs said. "We could play the catch technique, we could take a charge, I don't know, you gotta play football."

Trestman also said he expects defensive end Julius Peppers to play at Oakland on Friday, although he also noted he said the same thing last week. Peppers wound up sitting out his second preseason game because of a hamstring problem.

"We'll see where he is in pregame," Trestman said. "I'm encouraged based on what I saw here this week, he practiced every day, that he'll play."

Trestman also said receiver Earl Bennett and defensive end Henry Melton, recovering from concussions, are "getting better and making progress."

"We'll see what happens down the road, and we're going to try and be as upbeat as we can and stay encouraged that they'll be ready to go (for the opener)," he added.